Well, if you subscribe to the school of thought that you do need to change your setup due to different venues and you're insistent upon a pre-tune being necessary then it would make sense to me that you would need to do the whole process over again. Including time.
However, I don't think either is necessary, and certainly not adjusting for time since it's all relative. I think the issue isn't that the system changes but that our hearing is effected (for example, I've seen many cases where the drive/flight to finals has caused issues with people's sinuses). But, let's say you subscribe to those schools of thought... at the least, you could probably "get away with" just using the 2nd step of re-running DL to correct for your any atmospheric effects.
I agree with Erin.
Although I have driven to California from Colorado and had substantially more midbass it’s was about 3db , although everything seems to change together
And the balance wasn’t diminished in any way. But that’s a 5000ft drop in altitude. The mids and highs sounded the exact same.
It should sound mostly the same everywhere. I don’t think it’s quite enough to do a entire retune but depends how your system reacts (to farther the above)
If it were me I wouldn’t think it’s warranted