"There are, however, a couple of reasons why a faster payment into your Tally account may not be so fast - despite what the name suggests. The first is to do with the nature of Tally and the Faster Payment Network. This method of payment, however, was designed solely with traditional fiat currencies in mind. This means that every Tally customer has a GBP banking account which connects it to the traditional banking system, as well as the account which holds their Tally. Both are connected, but when a deposit is made, it first has to be converted into Tally. Normally this procedure happens within 2 minutes of the faster payment arriving, but as 1 Tally is 1 milligram of gold owned by the customer, held in a vault in Switzerland, a single large deposit, or an increased volume of deposits may result in a delay in your deposit.
In order for Tally to be deposited in your account, we must first purchase the gold via our LBMA accredited broker, and then allocate the gold (essentially verified as being physically purchased and moved in the vault) to Tally, which can take anywhere from a few hours up to 1 working day. In order to mitigate this we do maintain reserves of Tally (gold), but in the case of a very large deposit, or a dramatic increase in the number of deposits made, you may experience a delay whilst we go through the required steps to acquire your physical asset. The only way to completely guarantee this wouldn’t happen would be to issue Tally without corresponding gold in the vault, which is completely against everything we as a company stand for."
Basically, I’d always leave 1 full working day for deposits. If you deposit on Friday, that would be by Monday at some point.