==== Required information ====
- iRedMail version (check /etc/iredmail-release):
- Linux/BSD distribution name and version:
- Store mail accounts in which backend (LDAP/MySQL/PGSQL):
- Web server (Apache or Nginx):
- Manage mail accounts with iRedAdmin-Pro?
- Related log if you're reporting an issue:
======== Required information ====
- iRedMail version (check /etc/iredmail-release): 0.9.6 MYSQL edition
- Linux/BSD distribution name and version: ubuntu 16.04
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): MySQL
- Web server (Apache or Nginx): Nginx
- Manage mail accounts with iRedAdmin-Pro? Yes
- Related log if you're reporting an issue:  N/A
====

My SPF record has been up till now "v=spf1 mx mx:sydmx.net -all"
I have had to include an IP address for a couple of weeks as thee is another server delivering email from me to a specific group. the ip is 180.235.129.226   
SPF is confusing, shoul I change the SPF record in my DNS to  "v=spf1 mx ip4:180.235.129.226/32 -all" or
"v=spf1 ip4:180.235.129.226 mx mx:sydmx.net ~all"