Wikipedia states that 555-01xx are available for use in fictional works. Though this block of 100 numbers can presumably be stretched over all area codes, are there any larger blocks specifically reserved for testing/fictional/other usage, such as example.com, .test, 192.0.2.0/24, or 10.0.0.0/8. For example, would testing be a valid use of the 700 area code (paralleling the 10.0.0.0/8 block)?
Possible answer - NXX 958 and 959 are reserved for testing across all area codes, so using them for testing ideally should not be a problem, ie xxx-958-xxxx or xxx-959-xxxx.