Frantically pounding away on keyboard, to get a glitch fare OSL-PEK, when a colleague (who knew what I was doing) asked how long I was going for.

'One day' I responded...

Her reaction ... 'you should go for longer'

Brief pause while I considered. 'You're right' I said and carried on pounding.

'So how long are you going for?'

'Two days!'

Ok, I ended up going for a week, as the ticket was fully flex C for £220.

And my other 'you know when you're a FTer..:
When you are arguing with check-in staff about the configuration of the aircraft you are about to fly (I was right, although they thought they were being helpful)
When something goes wrong mid trip, and you have about 15 people in your phone you can call and go 'I need you to check what's happening to VS025 out of TAB as it's showing delayed and I don't trust the info. I'll text you my log-in details for BA as you may need to change my connection for me - it's a split PNR..' and they know what you are talking about and get right on it! The FT network is great in adversity...