A lot of women don't chart during AF, but it's recommended that you do, at least the first few cycles to give you a fuller picture of your cycle
Unless your AF is long, or you notice lots of EWCM mixed with it, you don't have to chart cm while she's visiting
Some women have a tad amount of fertile cm coming off of AF(as well as the 24hours before-hand), so you can watch for that, but don't be surprised if you don't get it, and/or it doesn't stay.
Do you mind if I ask how long your BF cycles have been?