Aren't you able to deposit the cheque at the ATM? ATM's are 24 hours and I usually do my deposits on the rare occasion that I receive a cheque.
even if you deposit on saturday, you will get the money on monday, so the 24/7 working is a big joke with atm
they are using those two days to work with your money and investing in assets it is well known...
It really depends on the bank and how long you've had an account with them. With my bank, some of the money would be available for use right away.