Image 1. Having completed 5 years and 146 days regular service, he was transferred to the Section 'B' reserve to complete his commitment for 12 years service.
Image 2. BTD x1 refers to the unit in the UK on whose strength he was being held pending his posting overseas, x1 refers to the X list (category 1): "The X (i) LIST comprises all ranks posted to fill vacancies in authorised War Establishments of a Headquarters or an extra-regimental unit (such as a base depot, school etc.)" BTD probably stands for something like Basic Training Depot. From here he "embarks in the the UK and is TOS MELF, then disembarks ME and is TOS this unit (ie the Composite Port Squadron). His rank is Sapper (ie private)
He is then posted to 53 Port Squadron and embarked at Suez and disembarked at Akaha (no idea where this was) in the rank of Lance Corporal.
He then went to the Royal Engineers Works Establishment Egypt where he as promoted from Unpaid (U) to the paid (P) rank of Local Corporal. Local in this context means that he was held (and paid) against a vacant Corporal position in the unit's establishment. It was not a permanent promotion and he would have reverted to Lance Corporal when he left the unit.
He was then TOS 11 DEL HQ from number 4 Detachment of the Port Operating Group. Not sure what DEL stands for here. In normal circumstances it means Directly Employed Labour ie locally engaged civilian labourers, which might apply here, in which case he would probably have been supervising these labourers.
Today 53 Port Squadron forms part of
17 Port and Maritime Regiment RLC in Marchwood and is no longer a Royal Engineers unit.