single word to represent the phrase "being available/helpful 24/7" in a team

I was just wondering if there was a single word to represent the phrase "something that is available/accessible all the time". The context for this is to thanks all the members of a team who helped to accomplish something and they were available 24/7 for the last few weeks.

Solution 1:

This concept is common in the IT world.

You could say the team was highly available. They had zero downtime. They offered five-nines support.

High availability is a characteristic of a system, which aims to ensure an agreed level of operational performance, usually uptime, for a higher than normal period. [...] Generally, the term downtime is used to refer to periods when a system is unavailable.
- Wikipedia

To be available “five nines" means to be available 99.999% of the time, i.e. unavailable 5.26 minutes per year.

You could use terminology regarding SLAs.

Service-level agreements can contain numerous service-performance metrics with corresponding service-level objectives. A common case in IT-service management is a call center or service desk. Metrics commonly agreed to in these cases include: [...]

• TAT (Turn-Around Time): Time taken to complete a certain task.
• MTTR (Mean Time To Recover): Time taken to recover after an outage of service.
  [...]

- Wikipedia