Battery charging during timed export

I have a Gen3 hybrid 5kW inverter and a 9.5kW Gen2 battery. I have two strings of panels, one facing SE and the other facing SW. I have a timed export setup from 6am to 9.15am. After this time I have HA set up to control the charge rate of the battery to stop the solar being clipped.
I have a tablet set up which displays the status of the system at a glance. I noticed this morning that the battery was being charged during the timed export period.

Has anyone else noticed this?

The only reason I can think of for this happening, is that the inverter is outputting the maximum AC that it can and has decided that it will send the remaining DC to the battery to avoid clipping. Despite the battery being set to export.

NormC yes, my system does the same. Scripts try to maintain SoC at a configured level and if it creeps up, turns on export. But it can only export when solar dips below 5kW, otherwise the battery charges, rather than discharges.
Rather than tweaking the charging rate, I just turn off eco when solar is strong - that in effect gives a grid-firsy policy, sending excess to the battery only when AC is maxed out.

DD I think this is a slighty different case. If it is going to be a good solar day then my system empties the battery from 06.00 and if it finishes before 09.15 it then normally sits idle until the time slot finishes. The battery started charging at 08.35 nearly 40 minutes before the end of the timed export was due to finish. I'll check last year's data to see if it happened at all then.

NormC not sure how it's different... Solar is generating 5.6kW (quite impressive for 8.44 am), but it can only turn 5kW into AC, so the rest has to go somewhere. During a timed export, eco is effectively turned off.

It isn't even like running more load in the house would mitigate this, as that would also be AC and your inverter wouldn't be able to convert that either. Any solar beyond 5kW must go into your batteries or be clipped, regardless of load. You could consider if you could install a larger inverter with a 5kW export limit but that would require loads in the house to use the rest and it is questionable if the cost of the change would ever be recovered. The obvious solution is more batteries but to pay back that would have to save you importing at other times.