The battery is dead, and about to be replaced but should I be aware or anticipate any issues once I reconnect the battery...

The car had been left in situ for about 10 weeks, has not moved, the handbrake has been left on, car was not started throughout the cold snap.

Am I going to suffer any issues with starting or immobiliser/alarm issues? (Mine does have a factory fitted alarm system)

Thanks in advance :-)

shouldnt think so probably the handbrake may stick a bit

Check your tyres for pressure/flat spots

If the hand brake been on for that long mate... good luck gettin it off. they are a pain after a week let alone 10. mine used to stick after a few days when I was based at Brawdy West wales . Made a right crack when I pulled away. after the 12 mile into H west tho it was ok again.