Hi Dawnie30
when MY JOB got made redundant (they cannot make you redundant) whilst I was on maternity leave these were my rights:
To be offered ANY job, even if there were more suitable candidates, within the company if there are any you could actually do.
AS far as I am aware you cannot start the redundancy process until your return. On your return you should then be either offered a job or given notice of redundancy then. They can either make you work your notice out from that point (I was put on Garden Leave to see if suitable vacancies appeared for six months with mine!) or offer you however many months notice you would be entitled to as money.
If the shop is shutting this week and the company is going bust then you may just need to take the money. My DH was made redundant and the company didn't have the money to pay him notice as well!
So you should get, if they have no job to offer you at all:
all you SMP entitlements
4 weeks redundancy (tax free)
your notice period as either work or money
your accrued leave as well as any outstanding leave you may have as paid days (taxed sadly).
They cannot make you take your notice period as hols - you are entitled to two sets of money and if you have been on leave for a year then you will have accrued another years worth of leave (or however many months you've been on leave)
Good luck. I've been through it rather than being a pro at this -if you get really stuck, try and employment solicitor as they will probably get you more money than you will need to pay them - it should only take a strongly worded letter to get it sorted!