Flying Club Econ->PE Reward Upgrade and Companion Flights

Hi everyone
Hopefully someone will know the answers to these - I will keep trying FC but they are very busy today (or is this the norm?)
We have a companion flight from VA AMEX and I understand that you pay a fully flexible fare and then your companion pays just the tax - is there a way of checking availability of the companion seat online - e.g. is it as simple as there being 2 flexi fare seats available or is it a flexi fare seat and a reward set or something far more complicated.
We also have a few E->PE reward upgrades - similar question - can I check availability online and also how do these work - is it miles required for the economy seats or can I pay for economy and use the upgrades.
Hopefully this makes sense?
Thanks
Hopefully someone will know the answers to these - I will keep trying FC but they are very busy today (or is this the norm?)
We have a companion flight from VA AMEX and I understand that you pay a fully flexible fare and then your companion pays just the tax - is there a way of checking availability of the companion seat online - e.g. is it as simple as there being 2 flexi fare seats available or is it a flexi fare seat and a reward set or something far more complicated.
We also have a few E->PE reward upgrades - similar question - can I check availability online and also how do these work - is it miles required for the economy seats or can I pay for economy and use the upgrades.
Hopefully this makes sense?
Thanks