Fearless has always been this way, you cannot use skills as herald during the time of fearless but you can put up defenses and use white hits (I generally use white hits to try and cancel people trying to f cap myself).
Also there's a possibility that you got canceled while casting fearless, like all cast time skills fearless is countered by silence, knockdown, fear the list goes on of things that cancel all skills.
As far as the some of your guild members part, I've not experienced that this patch with any of my guildees, you sure your guildees aren't lagging or something?
I know I shouldn't be able to do anything under fearless, but for some strange reason its effecting my guild mates. We were standing there with a bubble on and our thumbs up our butts, we couldn't do squat. Not even white damage. I didn't notice any lag during that moment.