Peugeot 207 Bleeder Valves location

[Onide207]

Hello, i am new on here and am looking for answers regarding the bleeding points on my Peugeot 207.

The System has already been flushed/cleaned and new Antifreeze is already in. I shouldve already reached the required 6l of coolant by now but i still have air in the system.
Now i have found the bleeding valve of the heater at the wall to the drivers cabin, but i am still looking for the other one which is supposed to be on the thermostat housing. Other sources say the bleeding valve should be right on top, but for me the heat sensor is there instead. Ill drop an image down below so you can see for yourself.

Alternatively a Peugeot-mechanic told me i could let the air out through the tank but that can take ages he said..

I really should get that air out, cant risk breaking the head gasket..

I would be happy for answers to my problem and appreciate your help!

[Onide207]

UPDATE: i have loosend the heat sensor and after some refilling it started to gooze out coolant. did the same with the one at the heater afterwards. i assume this eliminated the air pockets?

Will i have to do the same again when the engine reaches 90°C and the thermostat opens up?