The proper direction for a Les Paul bridge
The main reason anyone flips around the orientation of a Les Paul bridge is for extra intonation adjustment. But is that the correct thing to do? Let's find out.
Traditionally, ABR-1 has the intonation screws facing front towards the neck, and Nashville bridges have screws facing the tailpiece.
But let's say for the moment you wanted to flip the bridge around the other way. This is typically done with ABR-1 bridges because then you get some extra screw length to work with for intonation.
Is it OK to do this?
Whether you can safely do this or not basically depends on one factor. String saddle notches.
If your Les Paul bridge has string saddle notches that are sized on a per-string level, then no, you cannot flip the bridge around. If you do, the wound strings won't seat properly in the saddles and instead sit on top of them. The end result of this is possible buzzing noises and early string breakage.
If however your string saddles have notches that are all the same size, then yes, you can flip it around and you're good to go after setting intonation again.
Is there any tonal advantage to flipping the bridge around?
No. Flipping around the bridge isn't the same as top wrapping at the tailpiece (which I will probably talk about in another article later) that would affect how the guitar sounds.
Said again, the reason you do the flip is for extra intonation adjustment.
And yes, this means if your Les Paul is intonated fine the way it is, then you have no reason to flip around the bridge.
The annoyance of having the screws facing the tailpiece
A new annoyance that happens when you flip the bridge around is that it's more difficult to get at the intonation screws when they're facing the tailpiece...
...but this is only a minor inconvenience, because once your intonation is set, the saddles stay put. Unless you bounce around with string gauges (which most players don't), once you're done with intonation, you shouldn't have to do it again for a long time.
Gibson and Epiphone differences
Gibson Les Paul Standard 2019 model uses a Nashville bridge; the intonation screws face the tailpiece.
Gibson Les Paul Traditional 2019 model uses an ABR-1 style bridge; the intonation screws face the neck.
Epiphone Les Paul guitars for both the Standard and Traditional models use an ABR-1 style bridge with intonation screws facing the neck.
In fact, I am fairly certain all Epiphone Les Paul guitars with the bridge + tailpiece setup have ABR-1 style bridges on them, again with intonation screws facing the neck. When I scanned over all the LP models that Epiphone currently offers, I didn't see any with a Nashville style bridge on them.