Try with "update-help" (see REMARKS)...
I get following short information:
NAME
Start-CMDistributionPointUpgrade
SYNTAX
Start-CMDistributionPointUpgrade -SiteCode <string> -SharedDistributionPoint <IResultObject#SMS_MigrationDP>
-CertificateExpirationTimeUtc <datetime> -AllowPreStaging <bool> [-PublicFqdn <IResultObject#SMS_MigrationDP>]
[-InstallationAccount <IResultObject#SMS_SCI_Reserved>] [-InitiateConnection <bool>] [-InstallInternetServer
<bool>] [-ClientConnectionType <ClientConnectionTypes> {Intranet | Internet | InternetAndIntranet}]
[-EnableAnonymous <bool>] [-MinFreeSpaceMB <int>] [-PrimaryContentLibraryLocation <DriveType> {Automatic | A | B |
C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z}]
[-SecondaryContentLibraryLocation <DriveType> {Automatic | A | B | C | D | E | F | G | H | I | J | K | L | M | N |
O | P | Q | R | S | T | U | V | W | X | Y | Z}] [-PrimaryPackageShareLocation <DriveType> {Automatic | A | B | C |
D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z}]
[-SecondaryPackageShareLocation <DriveType> {Automatic | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O
| P | Q | R | S | T | U | V | W | X | Y | Z}] [-EnablePxeSupport <bool>] [-AllowRespondIncomingPxeRequest <bool>]
[-EnableUnknownComputerSupport <bool>] [-ComputersUsePxePassword <securestring>] [-UserDeviceAffinity
<UserDeviceAffinityType> {DoNotUse | AllowWithManualApproval | AllowWithAutomaticApproval}]
[-MacAddressForRespondingPxeRequest <string[]>] [-PxeServerResponseDelaySeconds <int>] [-ValidateContentSchedule
<IResultObject#SMS_ST_RecurWeekly>] [-ContentValidationPriority <Priority> {Lowest | Low | Medium | High |
Highest}] [-BoundaryGroup <IResultObject#SMS_BoundaryGroup[]>] [-AllowFallbackForContent <bool>]
[-PathForSavingMigratedPackage <string>] [-WhatIf] [-Confirm] [<CommonParameters>]
Start-CMDistributionPointUpgrade -SiteCode <string> -SharedDistributionPoint <IResultObject#SMS_MigrationDP>
-CertificatePath <string> -AllowPreStaging <bool> [-PublicFqdn <IResultObject#SMS_MigrationDP>]
[-InstallationAccount <IResultObject#SMS_SCI_Reserved>] [-InitiateConnection <bool>] [-InstallInternetServer
<bool>] [-ClientConnectionType <ClientConnectionTypes> {Intranet | Internet | InternetAndIntranet}]
[-EnableAnonymous <bool>] [-CertificatePassword <securestring>] [-ForceWhenDuplicateCertificate <bool>]
[-MinFreeSpaceMB <int>] [-PrimaryContentLibraryLocation <DriveType> {Automatic | A | B | C | D | E | F | G | H | I
| J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z}] [-SecondaryContentLibraryLocation
<DriveType> {Automatic | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W
| X | Y | Z}] [-PrimaryPackageShareLocation <DriveType> {Automatic | A | B | C | D | E | F | G | H | I | J | K | L
| M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z}] [-SecondaryPackageShareLocation <DriveType> {Automatic |
A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z}]
[-EnablePxeSupport <bool>] [-AllowRespondIncomingPxeRequest <bool>] [-EnableUnknownComputerSupport <bool>]
[-ComputersUsePxePassword <securestring>] [-UserDeviceAffinity <UserDeviceAffinityType> {DoNotUse |
AllowWithManualApproval | AllowWithAutomaticApproval}] [-MacAddressForRespondingPxeRequest <string[]>]
[-PxeServerResponseDelaySeconds <int>] [-ValidateContentSchedule <IResultObject#SMS_ST_RecurWeekly>]
[-ContentValidationPriority <Priority> {Lowest | Low | Medium | High | Highest}] [-BoundaryGroup
<IResultObject#SMS_BoundaryGroup[]>] [-AllowFallbackForContent <bool>] [-PathForSavingMigratedPackage <string>]
[-WhatIf] [-Confirm] [<CommonParameters>]
ALIASES
None
REMARKS
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