Hi,
Definitely not any hacking attempt.
ManageWP uses wide range of IP addresses as most of our services are distributed across several server instances and clusters. The IP in question is used by ManageWP for website management.
Here is a full list of IP addresses that ManageWP uses for normal operations: https://managewp.com/troubleshooting/general/managewp-ips-can-white-list
Also, in cases when 3rd party is providing the service – the requests may come from their range of IP addresses.
For example, ManageWP Uptime Monitor is powered by Uptime Robot. Most false positives happen when some of the IPs used to scan the website are blocked by hosting providers. To prevent this from happening on your websites you should make sure all the IP addresses Uptime Robot uses (https://uptimerobot.com/locations) are whitelisted.