Firstly, since it is being kept secret unreasonably, I reveal that the email address of Cambridgeshire, Bedfordshire and Hertfordshire police professional standards is bchpsd@beds.police.uk. They are legally required to process complaints sent to any police email address. But I do not know whether they will actually do this. They may consider that since they provide a web form to make complaints, this allows them to rewrite the law on what a complaint is, even though the form creates many problems, such as requiring a genuine street address, which makes it unusable for the homeless or people who fear revealing their street address. Cambridgeshire police used to advertise their old address: psd@cambs.pnn.police.uk as a place to send complaints, any decent police force would have emails sent to this address be forwarded to their new address, but instead, emails sent to this address are deemed not received.
Here, now, are some methods police professional standards departments may use if your complaint threatens the right of police officers to break the law with impunity, so you can be prepared and make countermeasures ready:
Having your complaint rewritten until it makes no sense is very common, as is replacing questions the police cannot answer with questions the police can answer. You may not find out about rewriting until a final letter when there is no chance to object.
The police have to send you a "final letter" when your complaint is closed. However, Cambridgeshire police do not think this letter actually needs to even mention the complaint at all. By treating any letter as a final letter, this allows them to close complaints without informing you.
Cambridgeshire police think it's acceptable to decide that you are lying without giving you the opportunity to present evidence, without even telling you they have decided you are lying. So if you report misconduct, and keep your evidence to yourself initially in order to catch them out when they deny it, they may not bother denying it, and use the tactic of a final letter which does not mention the allegation or reveal the complaint is being closed.
Even if you do get them to promise to view evidence, neither Cambridgeshire nor Bedfordshire officers think this means they have to comment on it at all, even to confirm that the evidence is as described.
Even if Cambridgeshire police ask you to wait for someone to be assigned to handle your complaint and promise you will be contacted for more information, their next act may be to send a final letter which does not mention the complaint.
If your complaint contains many allegations, Cambridgeshire police think objecting to a few of them allows them to ignore the rest. I do not know if you can prevent them from doing this by putting each allegation in a separate complaint.
Cambridgeshire police have this catch-22 situation when a long operation is ongoing. If you complain while the operation is ongoing, then you are using the complaint system to interfere with it. (No explanation of how the complaint would interfere is required.) If you wait until it's over, then you will be beyond the time limit. And if, having been accused of using the complaint system to interfere, you wait until it is over then make the complaint again, then it has already been decided to take no action.
A Bedfordshire police officer who says they understand a complaint when talking on the phone may say they do not understand it when they write their final letter. They will not ask for clarification.
Complaints sent to Cambridgeshire's old email address for complaints, psd@cambs.pnn.police.uk, are not, as you might expect, forwarded to their new address, they are instead deemed "not received". What is particularly outrageous is that they continue to state they cannot record the complaints because they have not received them even when sent to their new address, even when they respond, quoting the new complaints! Quoting the complaints they say they cannot record because they have not been received. Pointing out their legal requirements to record complaints gets ignored.