For us it wasn't so much broken naps but faffing around at BT, and nap resistance. Hence later nap, capped and same BT worked for us.
If your getting broken naps - if crying at 1 hr or so I'd say you've hit OT. If waking happy id push the nap a bit later.
If your getting BT resistance, NW wanting to play or 'cuddle' ie SA you could try a later BT, and wi/wo at NW.
We were really lucky in that when Z woke we could just given I'm a bottle and he went back to sleep, and it never became a prop. He also easy to read (for me) so I worked him out pretty quick.
You do have to make some small adjustments, then hold and try to ride it out. The 2 yr one I think lasted a few weeks here. It coincided with a huge language spurt.