after assessment centre but before getting the contract

Hi,

I will have an assessment center with Lloyds Banking Group (Scottish Widows‏) for an actuarial trainee position.

The assessment centre will be on mid-March.
The result of the AC will be known 1 week afterbthe AC.

However, I need to go back to my home country at the end of March for some personal reasons.

My question is:
Do I need to do any "pre-employment training, pre-employment project/assessment" before I get the offer?

If so, I don't think I can complete them before I leave the UK.

If not, every thing should be fine, and i will come back to here in August to arrange accommodation if needed.

Thank you