GSV shows that at Mascotte, the sigs on SB CR 33 say that it's SR 33 on the multiplex. The reassurance sign on SR 50 east of this intersection has only SR 50.
https://maps.google.com/maps?ll=28.57796,-81.884446&spn=0.000009,0.006196&t=h&z=18&layer=c&cbll=28.578099,-81.884523&panoid=yfTqAP43-YKePhIAICDKHg&cbp=12,213.75,,0,0 (https://maps.google.com/maps?ll=28.57796,-81.884446&spn=0.000009,0.006196&t=h&z=18&layer=c&cbll=28.578099,-81.884523&panoid=yfTqAP43-YKePhIAICDKHg&cbp=12,213.75,,0,0)
However, at Groveland, the signage on NB SR 33 says that it's CR 33 on the multiplexed portion. There is a reassurance sign west of the intersection that says WEST SR 50, NORTH CR 33
https://maps.google.com/maps?ll=28.557748,-81.851503&spn=0.000019,0.012392&t=h&z=17&layer=c&cbll=28.557748,-81.851503&panoid=HLI9vrz7u_9ryjd28otm3w&cbp=12,59.48,,0,0 (https://maps.google.com/maps?ll=28.557748,-81.851503&spn=0.000019,0.012392&t=h&z=17&layer=c&cbll=28.557748,-81.851503&panoid=HLI9vrz7u_9ryjd28otm3w&cbp=12,59.48,,0,0)
https://maps.google.com/maps?ll=28.558252,-81.85147&spn=0.000019,0.012392&t=h&z=17&layer=c&cbll=28.55834,-81.851442&panoid=F83I2c8LjPniI4_vAe9tUw&cbp=12,319.72,,1,0 (https://maps.google.com/maps?ll=28.558252,-81.85147&spn=0.000019,0.012392&t=h&z=17&layer=c&cbll=28.55834,-81.851442&panoid=F83I2c8LjPniI4_vAe9tUw&cbp=12,319.72,,1,0)
It's been this way for at least 15 years. The type of route 33 becomes where the overlap ends is consistently marked (even on SR 19).
I think this is further influenced by the one-way pair of SR 50 in Groveland. Each direction has its own section number, and Florida does sign concurrencies with two state roads until the road switches over to a county designation....that's probably why westbound SR 50 gets CR 33 and eastbound SR 50 gets SR 33.