Web interface not loading with v3.50 and 3.51

Hey PB team!
I’ve been having issue loading the PB3 web interface since updating to 3.50 and 3.51. Safari, Firefox, and Chrome all have similar issues where the loading square spins and the page never loads. Sometimes Safari reports error with “raw data received”… and Chrome has the spinning square with what appears to javascript behind it, ie:

e="0"> 7zM131(b ptbtmodalss="||eob)= p form-ga)>to UtniCon:hbl ue="0"> Wh.hasOwscr> nfb.RGB tn iCon: "+a ,astycsvabhturn new nxt(=, blob;do 5, c=p?coiCon:indolice,e=c.comxml:iCon> nindolice,e=c.comiCon> _te" id=c=c.urn new nxt(=,c==}a <%-na!1}Utnid="ou: blobTlShocav clo-lShocav cl29.9h width="cined.6-10(1rm-groidiorooidth="20%">Start...

I have one PBpico running 3.47 which loads fine and is responsive. Trying to downgrade to 3.47 on a PB3 seems to get stuck:

Running update, please wait. Pixelblaze will restart automatically when done. File 3/4 122320 bytes remain

And eventually says update failed. Reloading the IP immediately directs to /recovery.html.

Any help would be greatly appreciated!