Looking for advice on whether to adjust nap/bedtime during mild regression

We’ve always had a solid sleeper who typically sleeps through 90–95% of nights outside of the occasional regression. However, right now we seem to be in a mild regression — she has slept through 19 of the last 24 nights — but the pattern is trending in the wrong direction and starting to affect our confidence at night.

I’m trying to figure out whether the evidence suggests we should make an adjustment now, and if so, what is most appropriate:

Context:

She has always been a relatively high sleep‑need child. For months she has done well on a 5.5–6 hour wake window with a 1.5–2 hour nap. Recently she’s been having split nights.

She still sleeps through about 70% of the time, but any wake‑ups this month have been between 03:00–04:30, lasting up to an hour or slightly more. She doesn’t seem tired enough to fall back asleep quickly. She also seems to generally be sleeping lighter than usual.

She she settles herself unless she’s very upset, in which case we offer a quick cuddle. Final wake‑up is still around 07:30, so we’re not in a full sleep crisis, but I’m starting to get anxious and am myself sleeping poorly in anticipation of a wakeup.

Current routine:

Wake: 07:30

Nap: 13:00 (asleep 13:15–13:30)

Nap end: 15:00 (hard cut‑off; nap averages 1.5–1.75 hours)

Bedtime: 20:15 (asleep 21:00–21:30; this used to be 19:45 but we pushed it later during a regression in May ’25 and it helped)

Environment:

Dark room with nightlight

Cot bed with pillow + sleep sack

Room 20–22°C (she prefers cooler; house retains heat well; don’t think temperature is the issue)

Between the split nights, the long time it takes her to fall asleep at bedtime, and the long time it takes her to fall back asleep even when calm, I’m wondering if we’ve been coasting on what used to work and now need to make a small tweak.

Would love thoughts from others who’ve been through this.