Replace values in one column with another column value with condition across multiple columns

Hi,

I am asking for help to see if there is a better solution to the my current code

I am needing to replace a value in a column with a value in another column based on a condition but across multiple columns in a single step - I am not sure if this is possible - but I have 20 'pairs' of columns I need to do this for

My simplified sample code below is written for just 3 'pairs' of columns so has 3 steps but I would like to do it in 1 as they all reference the same 'condition' column

let
Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("lZNBC4IwFID/y84e3JxixyVqUcNWkal4UCSDOnTp/6dNYW6z3OANBu/7eG97KwpQuRFz7O8K43tDSQwsAO1uGwOJB1BaEyaC+5wSMaMP9xfRsoNKwJVwqOyAZ+MgSesXJRtVkg0SiEULMrRc1moppo4KUhJIDmzm8NLr0I0r3wsysGSR2s3EuqQd9qRkJ7/IGP5CyRFxia4ab5EjTNiNkqTLddCMSIO0HMG6dC1yPr05oozPPNI8+C/RPpge6edMnAn/H5FvJcJTiPID", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Id = _t, Working_Amount__c = _t, Standby_Onsite_Amount__c = _t, Standby_Offsite_Amount__c = _t, Working_Amount_s__c = _t, Onsite_Standby_Amount_s__c = _t, Offsite_Standby_Amount_s__c = _t, AllocationId = _t]),
ChangedType = Table.TransformColumnTypes(Source,{{"Id", type text}, {"Working_Amount__c", Int64.Type}, {"Standby_Onsite_Amount__c", Int64.Type}, {"Standby_Offsite_Amount__c", Int64.Type}, {"Working_Amount_s__c", Int64.Type}, {"Onsite_Standby_Amount_s__c", Int64.Type}, {"Offsite_Standby_Amount_s__c", Int64.Type}}),
ReplacedWorking = Table.ReplaceValue(ChangedType,
each [Working_Amount__c],
each if [AllocationId] <> null or [AllocationId] = "" then [Working_Amount_s__c]
else [Working_Amount__c],
Replacer.ReplaceValue,{"Working_Amount__c"}),
ReplacedOnsite = Table.ReplaceValue(ReplacedWorking,
each [Standby_Onsite_Amount__c],
each if [AllocationId] <> null or [AllocationId] = "" then [Onsite_Standby_Amount_s__c]
else [Standby_Onsite_Amount__c],
Replacer.ReplaceValue,{"Standby_Onsite_Amount__c"}),
ReplacedOffsite = Table.ReplaceValue(ReplacedOnsite,
each [Standby_Offsite_Amount__c],
each if [AllocationId] <> null or [AllocationId] = "" then [Offsite_Standby_Amount_s__c]
else [Standby_Offsite_Amount__c],
Replacer.ReplaceValue,{"Standby_Offsite_Amount__c"})
in
ReplacedOffsite

Thank you in advance