1) Will I be able to fly in the UK with JUST the SACAA PPL?
Yes & no. 8th April 2016 is the current cut off date, on & after which you will need an EASA licence to fly an EASA CofA aircraft. After that date your SA licence could only be used in non-EASA aircraft.
2) What is the process for converting a SACAA to EASA PPL?
Here's the regulation:
1. A PPL/BPL/SPL, a CPL or ATPL licence issued in compliance with the requirements of Annex 1 to the Chicago Convention by a third country may be converted into a Part-FCL PPL/BPL/SPL with a single-pilot class or type rating by the competent authority of a Member State. The pilot shall apply to the competent authority of the Member State where he/she resides or is established.
2. The holder of the licence shall comply with the following minimum requirements, for the relevant aircraft category:
- (a) pass a written examination in Air Law and Human Performance;
- (b) pass the PPL, BPL or SPL skill test, as relevant, in accordance with Part-FCL;
- (c) fulfil the requirements for the issue of the relevant class or type rating, in accordance with Subpart H;
- (d) hold at least a Class 2 medical certificate, issued in accordance with Part-Medical;
- (e) demonstrate that he/she has acquired language proficiency in accordance with FCL.055;
- (f) have completed at least 100 hours of flight time as a pilot
If the 100 hours is a problem there is an alternative route SA PPL --> NPPL SSEA --> EASA LAPL(A).
3) How long does the process take?
4) How much will the conversion cost once I return to the UK? (the PPL will already be in the region of £5K)
Minimal extra training + the skill test, so a few hours & a few hundred quid.