[BCM] [SAESL] [E1] [C5] Chapter 5: Determining BCM Assumptions for Singapore Aero Engine Services Private Limited

Introduction

Every business continuity plan is built on assumptions. A plan might assume that staff can reach the site, that power will return within a day, or that a supplier will deliver parts as usual. When those assumptions hold, the plan works. When they fail and nobody has noticed, the plan can collapse at the moment it is needed most.

For Singapore Aero Engine Services Private Limited (SAESL), with its specialised workforce, unique test facility and dependence on the wider Rolls-Royce Trent supply chain, the assumptions behind continuity planning deserve close attention. Chapter 1 listed a few example assumptions in passing. This chapter shows how to determine them systematically, record them in a register, test them and keep them current, in line with ISO 22301 and the expectations of the Singapore environment in which SAESL operates.

Why Assumptions Matter

Assumptions do three jobs in a business continuity management system (BCMS). First, they set the boundaries of planning: which scenarios the plans are designed for and which they are not. Second, they make planning possible, because no organisation can plan for every combination of events. Third, they expose hidden risks, because each assumption is a statement that could prove wrong.

ISO 22301 does not use a single clause for assumptions, but they run through several requirements. Clause 6.1 asks the organisation to address risks to the BCMS achieving its intended outcomes, and an unchecked assumption is exactly such a risk. Clause 8.2 asks for a business impact analysis (BIA) and risk assessment, both of which rely on stated assumptions about scenarios and timeframes. Clause 8.3 asks for appropriate strategies, which can only be judged against the conditions those strategies assume.

Categories of Assumption

SAESL will find it useful to group assumptions into categories. This makes gaps easier to spot.

Scenario assumptions

These define the type and scale of disruption the plans address. For example, SAESL might assume that plans cover the loss of one facility or one critical system at a time, but not the simultaneous loss of all Singapore operations. Stating this openly lets leadership decide whether a wider scenario also needs planning.

People assumptions

These concern staff availability and skills. For example, SAESL might assume that, in a pandemic, a significant share of staff could be absent at the peak, and that certifying engineers would be prioritised for on-site work. Singapore's Disease Outbreak Response System Condition (DORSCON) framework, used during COVID-19, gives a national reference point for the kinds of measures that might apply.

Resource assumptions

These concern premises, equipment and technology. For example, SAESL might assume that critical engineering data can be restored from backups within an agreed period, or that specialised tooling stored on site will survive a localised incident.

External assumptions

These concern parties outside SAESL's control. For example, SAESL might assume that its shareholders, Rolls-Royce Plc and SIA Engineering Company (SIAEC), would provide support in a major disruption, that utilities would be restored within a set period, or that customers would accept revised delivery dates if informed promptly.

Regulatory assumptions

These concern the authorities that approve SAESL. For example, SAESL might assume that its Civil Aviation Authority of Singapore (CAAS) approval and those of the other 12 authorities remain valid during a disruption, provided work and records continue to meet their conditions. Any plan that involves moving work, changing tooling, or using alternative facilities should test this assumption with the quality function before relying on it.

Determining Assumptions

Assumptions should be gathered, not invented by one person. A practical approach for SAESL has four steps.

1. Collect: during BIA interviews and workshops, ask each department, "What are you relying on that you have not mentioned?" Record every answer.
2. Consolidate: group similar assumptions and remove duplicates, so that, for example, several departments' assumptions about power supply become one assumption with several owners.
3. Challenge: ask a small panel, including the quality manager and a senior engineer, which assumptions they would bet the business on. Those they hesitate over need testing.
4. Approve: present the consolidated list to the BCM steering committee for approval, so leadership formally accepts the boundaries of planning.

The Assumptions Register

Approved assumptions belong in a register maintained by the BCM coordinator. For each assumption, the register records:

• A reference number and category
• The assumption, written as a clear statement
• The plans or strategies that depend on it
• An owner responsible for monitoring it
• How it will be validated, and when
• Its current status: validated, partly validated or unvalidated
• What happens if it proves false

The last column is often the most valuable. If SAESL assumes that a key supplier will continue deliveries, the register should say what the fallback is if it does not, even if the answer is "escalate to the steering committee".

Validating Assumptions

An assumption is only as good as the evidence behind it. SAESL can validate assumptions in several ways:

• Exercises: a tabletop exercise can test whether staff assumptions hold, for example by asking how many certifying engineers could actually reach site during a transport disruption.
• Supplier engagement: asking key suppliers about their own continuity arrangements tests external assumptions directly.
• Technical tests: restoring data from backup tests assumptions about recovery times.
• Regulatory dialogue: the quality function can confirm with CAAS how its requirements would apply to a specific alternative arrangement.
• Experience: lessons from past events, such as the COVID-19 pandemic, show how assumptions behaved under real stress.

Common Pitfalls

Several mistakes recur across organisations, and SAESL can avoid them by name.

• Optimism bias: assuming the best case, such as full staff availability or immediate utility restoration.
• Hidden single points of failure: assuming a resource is replaceable when it is not. The engine test facility, for example, may have no ready substitute.
• Stale assumptions: assumptions that were valid when written but have since been overtaken by changes in staffing, suppliers or systems.
• Unowned assumptions: assumptions nobody is responsible for checking.

Summary Table

Table 5: Determining BCM Assumptions for Singapore Aero Engine Services Private Limited

Conclusion

Assumptions are the foundations of SAESL's continuity planning. Made explicit, recorded, owned and tested, they give leadership a clear view of what the plans can and cannot handle. Left implicit, they become hidden risks that surface only during a real disruption.

With assumptions approved, SAESL has the direction it needs. The next step is to decide who will carry out the work, which is the subject of Chapter 6.

Continue reading: Chapter 6, Composing BCM Team for Singapore Aero Engine Services Private Limited, sets out the roles, responsibilities and structure SAESL needs to run its BCM programme.

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