Will root stock alter blooming time?

I have a Tilton apricot grafted on my ornamental red leaf plum. I noticed a week ago small portion of its flower buds showed pink petals while my other apricots are still in deep slumber. I went out checked these flower buds again today, after recent cold spells, they are still in the same stage as they were a week or so ago. Didn’t see cold damage (we were down to 22 at night). I also checked Tilton blooming season, according to DW, it is supposed an late season bloomer. I couldn’t think of any reason for this apricot to wake up so early but to think the root stock altered it.
Ornamental red leaf plum does seems a early raiser, so cultivars I grafted in it will synchronize with root stock’ waking up schedule/timing?

Although, the Tilton apricot was bought from big box store many years ago, from Lowe, HD, I don’t remember. I gave it to my sister, and she grew in her back yard till it bloomed and fruited. The first year it set few fruits , squirrel harvest them all, the second year it set fruit I got tasted a wormmy but very ripe one, that was very sweet , juicy , aromatic. I took cuttings but I don’t have good branch to graft it on so I gafted it on my red leaf plum without knowing if they are compatible, etc. Luckly, it survived. My sister’stree died suddenly the following spring, leaf withered suddenly. I was very glad I saved a stick.
For three years it has been blooming on the red leaf plum ,I noticed, it usually blooms few days earlier than my Robada. But since it’s flower buds do not all bloom at the same time, there always some I can pollinate with Robada.
This year its bloom seems exceptional early. I start to wonder did I get wrong cultivar or just because it is on red leaf plum. I now have 6,7 various J plum, pluot, apricot grafted on the red leaf plum, and some might need to be pollinated. My dilemma is how should I match the bloom time if the root stock will alter its blooming time. Any suggestions??

I am no expert but I would think that the scions would wake up when the roots start pushing the sap. So my vote is yes, the rootstock would influence blooming time to a degree.

I would think, however, that all the plums on the same tree would wake up according to their original bloom sequence. I have apples on one tree and not all the scions bloom or even leaf out at the same time, but I assume they are still blooming in order of Early, Mid, Late. I will have the make a note of that when they start to bloom.

There is a research report discussed in another thread that shows a small effect on bloom time based on choice of rootstock. The research centered around testing various plum roots roots for prune plums. It seemed that the maximum change in bloom time was less than a week at most with the majority of test plant blooms occurring within a day or two of each other. Here is the link to the previous thread Rootstock vs onset of bud break? - #14 by danchappell

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This has been asked many times. The answer is clearly Yes and No.
The branches and grafts have there own energy stores. Regardless of when the rootstock wakes up the grafts could wake up earlier then there hosts. This is likely why otherwise hardy fruits like apricots die suddenly due to root and branch being out of sync.