Serving order for primary subjects - is random possible?

[tufixm]

Is there any way to have the primary subjects being served randomly to different annotators?

My second question is about the order in which the primary subjects are served when we divide them into groups. For instance:
Group A: subj_a1, subj_a2, subj_a3
Group B: subj_b1, subj_b2
Group C: subj_c1, subj_c2, subj_c3, subj_c4
The way I see subjects are served right now is: a1, a2, a3, b1, b2, ...
However, it is not possible for annotators to move, for example, to Group C, before finishing Groups A and B.
Alternatively, what is the way in which we could direct annotators to a given Group, in the way it is done in the Old Weather project, after annotators select the ship which they want to annotate.

Thank you!