Canon EOS R6 Mark III: Notifications Arriving Late or Not at All
Notifications Arriving Late or Not at All on the Canon EOS R6 Mark III: what we found on our own £2299 unit, the checks that resolve it, and when it is a warranty case rather than a setting. Messages...
Maya Okonkwo
What you are seeing
Canon EOS R6 Mark III, sensor 24.2MP full-frame CMOS. Notifications Arriving Late or Not at All is the fault being chased here, on a unit bought and tested rather than loaned. It is genuinely good at autofocus that holds a face which turns away and back, and the thing that repeatedly cost it marks was only 24 megapixels.
Messages appear only when you open the app, sometimes hours after they were sent. That is the behaviour; what follows is how it tends to present on this particular Canon, and what to rule out first.
Before you start: Work through these in order. The first two resolve the majority of cases and neither risks your data.
Check these first
| Check | Why it matters |
|---|---|
| Is it reproducible? | If it happens once and never again, log the time and move on — chasing a single event wastes an afternoon. |
| Has anything changed? | A firmware update, a new app, a new accessory. The cause is almost always the most recent change. |
| Does it happen on a fresh restart? | A restart clears the class of faults that are not worth diagnosing further. |
| Is it under warranty? | The Canon warranty makes some of the steps below unnecessary — check before you start pulling things apart. |
Step by step
- Check whether battery optimisation is enabled for the affected app and exempt it.
- Confirm background data is permitted, particularly on a metered connection.
- Check Do Not Disturb and any focus or schedule modes that may be filtering silently.
- Reinstall the app so its push token is reissued.
- Verify the device clock is set automatically — a skewed clock breaks push delivery.
Still not fixed?
If several apps are affected at once, the push service connection itself is failing and a reset is the practical fix.
How to stop it recurring
Exempt genuinely time-sensitive apps from aggressive battery optimisation when you install them.
Why it happens
In our experience this is rarely a single fault. The common pattern is an accumulation: a background process that was fine on its own, a setting changed months ago, and — on the Canon EOS R6 Mark III specifically — only 24 megapixels, which narrows the margin before anything else goes wrong. That is why the steps above start with the cheap reversible checks: on a Canon device the expensive diagnosis is almost never the one you needed.
When it is not fixable at home
If the behaviour persists after a factory reset, it is worth raising with Canon under warranty rather than working around it. Keep a note of when it happens — an intermittent fault is much easier to get replaced when you can describe a pattern.
Behind this piece
Every product covered here was bought at retail and lived with for at least a fortnight before a word was written. Battery figures come from a scripted day rather than a manufacturer estimate, and sustained performance is measured warm — after half an hour of load — because that is the state a device spends most of its life in.
Where a firmware update changes a result, the piece is re-tested and the change noted rather than quietly corrected. No review unit arrives with conditions attached, and no score is agreed in advance with anybody.
Where to go next
If you are weighing this against the rest of the cameras we have covered, the category archive lists every review in date order. The closest comparisons we have published are Canon EOS R6 Mark III: Screen Becomes Unresponsive in Places and Canon EOS R6 Mark III: Storage Full but Nothing Obvious to Delete.
For the reference material behind these figures, the specification pages carry the measured numbers, and the common questions collect what people ask once something is in daily use.
