If it's an external company like Cyclescheme or similar, then you'll have to order a complete bike, and you're unlikely to be able to top up. If it's run internally, then they'll just hand you a cheque made out for whoever you ask for, and ask for a receipt so they can claim back the VAT. I topped up to get my road bike, and got a receipt that had the bike listed at £1,000 and my "deposit" of £250 listed separately. The vaguer the receipt is, the better.
All depends on the scheme.
If it's an external company like Cyclescheme or similar, then you'll have to order a complete bike, and you're unlikely to be able to top up. If it's run internally, then they'll just hand you a cheque made out for whoever you ask for, and ask for a receipt so they can claim back the VAT. I topped up to get my road bike, and got a receipt that had the bike listed at £1,000 and my "deposit" of £250 listed separately. The vaguer the receipt is, the better.