As @egarro stated, all [most] newer products support [only] the newer and improved TVP archietcure. QFX5100 was only product in QFX family that was caught with support for 2 archiectures. To keep backwards, as well as forward, compatiabilty for mixed VC and VCF, for the QFX5110 (the Spine in VCF) 5e is explicately called out as "informational". Reason is:
You can not mixed in the QFX5100/5110 family a 5e and a non-5e in any mixed VCF/VC. QFX5110 will call out 5e explicately for this reason, while all [at least most] other products supporting the newer TVP archiecture will not.
Once you convert any QFX5100 to 5e TVP archiecture, that switch can now ONLY be used with other 5e switches, in a VC or VCF, and return to non-5e is not supported. This is all informational [warning?] so that [only] QFX5100 customers do not run into issues.
The details of the archiecture are Juniper propritary as is the SW archectuture for Junos or newer EVO.
HTH