Just an update on this incase it helps anyone on the future.
Car is in garage with burnt out exhaust valve. can only presume this was the cause of gradual increase in oil consumption.
Ended up with bad miss-fire on cylinder 1, Diagnosed initially (AA man) as a coil pack failure which sounded a nice simple and cheap fix. I have the AA Breakdown Repair Cover(BRC) so took the car to the nearest Halfords auto-centre as they link direct to AA BRC so easy to claim. After replacing coil pack the miss-fire was still occurring. Took a deep breath and suggested head came off for diagnosis of valve problem.
have ended up with 4 new valves in cylinder 1, new oil stem seals all round, skim, new timing belt kit, water pump, etc etc. grand total of £1300 but AA paid £500 (had to show all previous service invoices to get them to agree on payout).
The cars an 02 plate 147 2.0TS so probably not really worth the spend but I'm very attached to it and at least i know that I've got a new top end now in a car that been very well looked after.