Gradual retreat - now what?!

[PetrovaFossil1]

Can anyone help advise what a next step might be. Our 21 month old has been happily self settling and sleeping through since he was 6 months old but seemed to get a bout of esteem separation anxiety in November and suddenly needed someone holding his hand to get to sleep for naps and bed.
We've used gradual retreat so we're now outside his door but he calls out to us about every 2 mins for 30-45 mins until he goes to sleep. He's also waking in the night at times still but will go back to sleep if someone pops in to reassure him.

Can anyone suggest how to gradually retreat further from this, since he already can't see us!

You gradually increase the time between your returns to the room. For example the first 3 nights you go back every 5 minutes, then increase to 10.

You could take it as slowly or quickly as you want. So maybe not increase the interval of check backs as regularly, but I think if you took it too slowly each step may be harder to transition out of.

Is he very upset going to sleep? Or just wanting reassurance? I’d let that be your guide as to how often you go back and how quickly you increase the gaps between returns.

Do the same thing for night wakings if you need to (doesn’t sound like it), but I wouldn’t respond at all for 10 minutes. That gives him time to try and settle himself.

We are in week two of gradual retreat, but with a much younger baby.

What do you do when he calls out?

At the moment I reply that I'm still there. He usually says 'mummy stay!' And I'll reply. If I don't he'll repeat it with escalating volume.
Although I haven't tested out not replying for more than a minute or so...

My son has had a bit of an upset at bedtime recently, what Iver done is put him in his cot, settled him down (as in not asking to get out) then I say "just going to get a tissue, back in a minute" and do go back. And repeat. Could you try this except from outside? "I'm still here ds but I'm just going to the toilet, I'll be back here in a minute" etc.