I use Revolut to HSBC to fund my card spend. The FX risk means for particularly chunky purchases, I hedge straight away especially should there be a huge swing in the currency against me. Sometimes, I'm tempted to wait. I put a large (by my standards) charge on Saturday on my US Amex and bought the USD on Revolut within minutes - I had a good feeling the AUD would rise closer to 70c and it has but I think risk management is key especially when we're doing this for the points. I left the USD in Revolut most of the week and transferred to HSBC last night. I've previously got the "don't use us as a money transfer service" email so leave it there for a few days so it's not entirely obvious what I'm doing and Revolut gets to make some $$ from my interest free funds. YMMV.
