"On" is more often used to describe someone who is in the process of taking part in a call more generally. "Will you be on that call this afternoon?". But you could equally say "in" here. The phrase "on a call" can also mean making a visit, usually an official one.
Consequently, are you on call meaning?
on call. phrase. If someone is on call, they are ready to go to work at any time if they are needed, especially if there is an emergency.
Likewise, can we jump on a call?
The phrase "I'll jump in the call" -- or probably more common: "I'll jump on the call" -- means you are joining the conference call. The modifier "jump" connotes you are possibly joining at the last minute, or joining due to an urgent request.
What is the purpose of on call?
On-call scheduling, sometimes referred to as on-call shifts are processes used in business where employee work schedules are intentionally unpredictable. Employees who work on-call are expected to be available at any time during their shift, usually with short notice, to carry out their working duties.
What does jump on a call mean?
Jump on a call: 1. Join a conversation on the phone. 2. Strangely energetic phrase suggesting that stringent physical action is somehow involved in the simple business of having a chat; a close cousin of jumping on an email, which sounds positively inadvisable.