@psaghelyi 

Hi, nice to see you again. I saw you followed the other post and thought your model is Deco M4. So please ignore the debug firmware for Deco M4 v4.

As mentioned earlier, I can assure you there is no such limitation.

Could you please help me check the rest of the information here:

https://community.tp-link.com/en/home/forum/topic/584162?replyId=1138540

Thank you very much.

  @Cstoth 

Hi, Did you also have Deco E4?

Both the hardware and firmware have come out for quite a while and I haven't received similar feedback before. So I tend to think there isn't a limitation.

Do you also have a lot of smart home devices? 

Could you please refer to the following suggestions:

1. leave the main network on 2.4ghz only and turn off 5ghz.

2. enable guest network for 5ghz only.

3. connect the smart home devices to the main 2.4ghz network, move the normal network devices, like smartphones and laptops to 5ghz guest and check whether you are able to reach over 10 clients.

Thank you and wait for your reply.

Best regards.