AWS Cloudformation "Include" transform issue - amazon-web-services

Question

AWS Cloudformation defines Transform section on global template level as an array.
See Transform section definition here.
I created two entries in Transform section that include some partial definitions of stack resources.
The goal is to create a few files with definitions/resources grouped by "product domain" per file.
When I create stack based on this template it executes one partial definition only (the last one - other definitions with "AWS::Include" name are ignored or "overridden")
This is the main template definition:
{
"AWSTemplateFormatVersion": "2010-09-09",
"Description": "Test of json file inclusion",
"Parameters": {
"Environment": {
"Type": "String",
"Description": "Specify Environment: prod | dev ",
"AllowedValues": ["prod", "dev"],
"Default": "dev"
}
},
"Transform": [
{
"Name": "AWS::Include",
"Parameters": {
"Location": "s3://a1-local/cf-tests/part-1.json"
}
},
{
"Name": "AWS::Include",
"Parameters": {
"Location": "s3://a1-local/cf-tests/part-2.json"
}
}
],
"Outputs": {
}
}
This is part-1 definition
{
"Mappings": {
"MappingForBucket1": {
"eu-west-1": { "AZs": [ "eu-west-1a", "eu-west-1b" ] }
}
},
"Resources": {
"hellobucket1": {
"Type": "AWS::S3::Bucket",
"Properties": {
"BucketName": { "Fn::Sub": "as-testbucket1-${Environment}" }
}
}
}
}
This is part-2 definition
{
"Mappings": {
"MappingForBucket2": {
"eu-west-1": { "AZs": [ "eu-west-1a", "eu-west-1b" ] }
}
},
"Resources": {
"hellobucket2": {
"Type": "AWS::S3::Bucket",
"Properties": {
"BucketName": { "Fn::Sub": "as-testbucket2-${Environment}" }
}
}
}
}
How to join/chain multiple transformations in such case?