Hi there
Just looking at your routine - you say you count his day as starting from 6 when you gt him up, but what time is he actually waking? Is it still 5ish? It is posible that he needs another A push - LOs can quickly increase their A time at this age - but there's alo a lot of developmental stuff going on, a growth spurt, teething, and often LOs are really getting going with solids... Not to mention the 3-2! So it's common for sleep to go wrong at this age and it's not always routine related. For Jack, a 10.5 hour night was standard for a very long time - even now 11 hours is the best we get unless he's really OT. A lot of that stopped cos he just got older I think and all those things also stopped or slowed down.
Has he started solids recently? Do you think he could be hungry still? Perhaps it's time to introduce an evening meal as well - unless you're very early days in which case you might not want to rush it as starting solids can disturb sleep in itself. is he having a night feed still? Any teething? That always caused EWing here.
How long has he been EWing / NWing? If it's been going on for a while it could be more than developmental... You say he's getting tired - do you think that's cos his A times are too long (is he getting tired before his nap?), or do you think it's general tiredness from a short night? Some LOs need a longer morning or evening to avoid NWs - do you have a feel for which your LO might prefer? If increasing your A time recently has improved the NWs at 12, then it might be he just needs a further push to get rid of the EW too. Certainly with Jack that's the order of fixing things, anyway! NWs normally go first, and then EWs when we push A times.