Why can't you transfer in one go with Wise? I thought Bangkok Bank and Kasikorn you can transfer up to Bt3m and SCB 1,499,000? UK banks limit the transfer size with larger sums being transferable from laptop/PC bank access and smaller amounts via phone apps as far as I know.
Wise is very easy, arguably easier than banks. Wise are generally quicker, offer better rates and can also be flagged as international transfers so long as you select the relevant reason for transfer?