hls_capleveltostage cause not immediate switch when going fullscreen with flashls OSMF plugin

Our player has hls_capleveltostage implemented. What I am seeing is that when hls_capleveltostage is true and I am going fullscreen the player does switch to a higher bitrate as the stage permits it (network logs show the higher playlist is loaded) but it does not flush its buffer of previously downloaded segments immediately and play them before actually displaying the higher bitrate segments. Is this the correct behaviour? Should not the higher rendition segments be displayed immediately when going fullscreen rather than waiting for the previously downloaded segments to be playback?

I am using v0.4.4.21 flashhls plugin for OSMF with Flash 21 on Chrome or Firefox.

Thanks