Pretty sure too 
There are (from memory) 10 or 12 envelopes
All are paired, one has a restart from zero (the dotted ones), the neighbouring one is start from where you are currently (i.e. Amp Level)
Most are variations of the same, but have different slope profiles exponential or linear for different envelope feels during the attack and decay/release stages
Sometimes, depending on how long you trig or press a note, you may go straight from the Attack to the Release phase, generally if you hold a note longer it’ll go into the decay, then sustain, then release phase - so even with identical envelope settings it is possible to play the envelope two different ways, depending on the brevity of the input note (set sustain to zero)
The more unusual envelopes are nominally for percussive type usage cases, these are the latter ones, they use no attack phase as such, but translate the attack value into a sorta hold value at the start phase of the envelope (very useful)
the best thing you could do is experiment, maybe even just record the output of the same env values through different shapes to see the basic profiles in a DAW or editor
To explore the subtleties of the dotted envs, you need to have longer envelopes and try to play before the last note finishes, note the difference to the attack if the previous env has not decayed
Have a peek here for geek talk