Or you can be really naughty and edit the appropriate ini.file (or use sh3 inspector) to fine tune your Uboat to travel 5 time faster than they could historically.
I made myself a turbo charged IXC that could reach 70 knots surfaced... Just a bit of fun, but really but if you want to hunt for tasksforces its the only way to catch them.
Other wise you gotta do what the real kaluans did - hope you happen to get that 1 in million chance where a TF magically crosses your bow at 2000 meters... Thats the price of realism for you.