Kirstey,
Last time I was issued with a TAC it was only valid for a finite time (90 days I think but long since binned it), we would obviously hope that 3 months would be more than enough time for them to issue your licence though.....errr ok.....
The TAC is simply a single sheet piece of paper filled in by the examiner on sucessful completion of your test, the pucker licence is a errrr....slightly smaller single sheet piece of cardboard. At least now I know why the UK licences as so much more expensive....all that plastic with pockets in them and extra bits of paper....very costly...
Julian