Normally when I top my Thai funds up from my UK account, I do it £10K at a time. This has always been a safe amount to transfer. Due to Brexit fluctuations, I have not transferred for sometime. However, funds are dwindling, and visa extension time is looming - I need to transfer funds soon, or sell my body

if I sell it by the kilo, I could become rich

.
Seriously, I know £10,000 was a safe amount to transfer, but this time it won't be enough. Are there any restrictions on transferring maybe £20,000 in one go please?