5.1.2 to 5.1.4 upgrade path
I’m currently mapping out an in-ceiling Atmos installation for a 5.1.2 setup, but I want to future-proof the placement so I can upgrade to 5.1.4 down the road without having to move the first pair of speakers. The space is an open-concept living room. The listening area itself is 4m deep, 3m wide, and 2.8m high. There is no right wall (it opens up into a dining area).
The sofa is against the back wall, but due to the cushions, the actual main listening position (ears) will be about 40cm away from the back wall.
Surrounds will be on articulating mounts on the back wall, angled in toward the couch.
I bought a pair of 6.5" in-ceiling speakers with pivoting tweeters for height channels.
My original plan was to go with 4 height speakers but due to the proximity to the back wall I am afraid of putting the top rear pair 40–50cm from the back wall because of wall reflections. Because of this, I want to start my 5.1.2 phase by placing the first pair as Top Middles. My thinking is to place them 100cm out from the back wall. This avoids the wall reflection and puts them within the Dolby spec for 5.1.2.
My question is if I decide to upgrade to 5.1.4 in the future, could I re-designate this 100cm pair as my Top Rears (even though they are technically slightly in front of the MLP) and then place the Top Front pair closer to the TV (around 2.5m–2.8m out from the back wall)?
Will this forward-shifted array still pan properly, or am I better off sticking to just 2 Atmos channels?