Update: right then picked the battery up this morning (after ringing them to find out what was going on - told it was ready to collect). Picked the battery up and they assured me they had re-charged it and it was sound, so good result as there was nothing to pay (still inside 3 year warranty). When I got it home I thought the green light in the bubble indicator looked a bit dim so I checked the voltage across the terminals with a multimeter and it indicted just shy of 13.1 Volts so I'm happy with that.
Busy today with the family so tomorrow I can start re-fitting my oil cooler as the forecast is for Saturday to be the best day of weekend.
I will check out the maintenance guides as suggested by Kevin as well - cheers