Hi Zappy
Time outs will occur based on the amount of data that AccountRight is processing in the background. When it comes to bank feeds, previously approved bank feed transactions are stored in the file. If you've got a high number of bank feed transactions stored, say a large account or a few years worth, this can slow down AccountRight as it needs to sort through all that data.
If the timeout extender doesn't help the issue you can send me the serial number and primary contact name in a private message and we can have a look at the file size.